As a next-generation system of the W-CDMA (Wideband Code Division Multiple Access) system and the HSDPA (High Speed Downlink Packet Access) system, an LTE (Long Term Evolution) system has been studied by the standards body referred to as 3GPP (3rd Generation Partnership Project). In the LTE system, a single carrier scheme (SC-FDMA: Single-Carrier Frequency Division Multiple Access) has been studied to be applied to uplink communications (see 3GPP TR 25.814 (V7.0.0), “Physical Layer Aspects for Evolved UTRA”, June 2006, for example).
FIG. 1 shows an exemplary configuration of an uplink communication channel in LTE. As shown in FIG. 1, the system band is divided into plural frequency blocks. The frequency block is also referred to as a resource block, which is a minimum unit for assigning a band. In addition, the time domain is divided into transmission units referred to as subframes. The subframe is further divided into two slots.
The uplink communication channel includes an uplink shared channel (PUSCH: Physical Uplink Shared Channel) and uplink control channels A and B (PUCCHs: Physical Uplink Control Channels). User data are transmitted on the uplink shared channel. The uplink shared channel is also referred to as a data channel. Control information such as channel quality information (CQI: Channel Quality Indicator) used for AMC (Adaptive Modulation and Coding) and PMI (Precoding Matrix Indicator) representing antenna weights in the case of MIMO (Multiple Input
Multiple Output) transmission is transmitted on the uplink control channels A and B. It should be noted that the uplink control channels A and B are mapped to different positions in two slots within a single subframe (frequency hopping is applied) (see R1-070100, “CDMA-Based Multiplexing Method for Multiple ACK/NACK and CQI in E-UTRA Uplink”, January 2007, for example).